Compass is defending its productivity claims from attacks made by MoxiWorks, a “competitor” that CEO Robert Reffkin says is “trying to damage our reputation.”

In a comment to Inman Thursday, Compass CEO Robert Reffkin noted that investors have given his company “hundreds of millions of dollars” and “didn’t just take our word for it.” He also said that Compass has been evaluated by a third party, which verified the company’s claims.

“A third party accounting firm, Ernst & Young, was hired and performed an independent analysis of our financials and verified the numbers,” Reffkin said.

The comments come in response to claims from MoxiWorks, an open real estate tech platform, that its agents reported productivity declines after moving to Compass. MoxiWorks began digging into productivity at Compass after Reffkin made several controversial claims in a June CNBC interview, including that his agents net a 24.9-percent boost in transactions in their first year.

MoxiWorks has also criticized Compass’ market share claims and its characterization of its place in the real estate ecosystem.

In his comment Thursday, Reffkin pushed back against MoxiWorks, though he did offer some faint praise of the company.

“MoxiWorks is a company that sells software to brokerages and agents, and considers Compass a competitor so I understand why they are trying to damage our reputation,” Reffkin said. “Moreover, our largest region is NYC which doesn’t have an MLS so they can’t even access our agents business in those markets. That said, I respect MoxiWorks and they have built a strong product that they should be proud of.”

Despite the pushback against MoxiWorks, Reffkin has expressed regret about the tone of his company’s public persona. In an interview earlier this week with Inman, Reffkin said his company had used “arrogant” marketing language.

“That’s not who we are as a company,” Reffkin said. “That’s not who I am as a person.”